<script setup lang="ts">
import { reactive } from 'vue';

// 默认推断
// const book = reactive({title: '老韩教vue3'})

// 我们想要的数据类型是  {title: string; year?: number} 
type Book = {title: string; year?: number} 

const book: Book = reactive({title: '哈哈', year: 1111})
</script>

<template>
  <div class="app-page">
    app
    
  </div>
</template>

<style lang="scss" scoped></style>
